@misc{indiciae6a1a3e41713a,
  title = {GSDRAW and GSMAP version 4.0; prototype programs for the IBM PC and compatible microcomputers to assist compilation and publication of geologic maps and illustrations; A, documentation},
  author = {G.I. Selner and R. B. Taylor},
  year = {1987},
  doi = {10.3133/ofr87496a},
  url = {https://pubs.usgs.gov/publication/ofr87496A},
  note = {Source identifier: ofr87496A}
}